Matt Helsley [off-list ref] writes:

	Seems like an ok concept to me. Did you try doing this with
anon_inodes and bind mounting the /proc/<pid>/fd/N as above to keep
them alive and name them?

Of course this part doesn't work in my patch because I have the wrong
mnt_ns on my mount MS_NOUSER on my superblock.

MS_NOUSER is easy to get past.  Getting a vfsmount in the proper mnt
namespace could be tricky.

Eric